All posts by Lenore Edman

About Lenore Edman

Co-founder of Evil Mad Scientist Laboratories.

LED Metronome


After seeing our Larson Scanner kit, Martin shared this LED metronome project with us. Martin says:

It was designed as a “Visual Metronome”  So a learning music student could help see the timing by watching the green light.  There was to be an optional clicking sound  by using a small solenoid for the ticking – I chose that in place of a speaker for a more authentic sound.

The timing is a standard 555 timer which is fed to 7442 BCD to DECIMAL counter.  Next chip is a 74193 UP/DOWN counter.  When the count hits the last number, it sends a pulse to reverse the count or start over – depending on the toggle switch on the side.

There is also a pot on the 555 to control the speed.  All this was made in one night while I was working the graveyard shift.

The entire LED display was hand wired using a manual wire-wrap tool.

The chip pin labels on the back of the perf board are a particularly awesome relic of a different era of electronics assembly. Thanks for sharing your project photos and video with us!

DIY Snowflake Chocolate Molds with the Othermill

Our friends at Other Machine Co. have put out a mold making kit for the Othermill and posted an instructable for making snowflake chocolates using the online Snowflake Generator that Paul Kaplan of Inventables ported from our Vector Snowflake Application.

The process involves milling a wax positive for making a silicone mold. The beautiful two-tone chocolates are made by putting white couverture chocolate into the details of the mold, and then filling the rest of the mold with dark.

One more technique we could have used for Operation: CNC Snowflake!

How Computers Compute

The Digi-Comp II we made for MIT is featured in this outreach video from MIT+K12 Videos by Jamie Teherani about how computers work. The mechanical switches on the Digi-Comp II are compared to first to light switches and then to transistors. Regarding manufacturing computers with transistors, Jamie says, “We can make them over a billion times faster than the Digi-Comp!”

CNC Dragonfly Barrette

Dragonfly Barrette

When I saw Simone from Othermill running her machine this weekend, I told her about an idea I had for a metal dragonfly hair clip. She quickly grabbed the file from Sam DeRose’s Light-up PCB Pins tutorial. After carving the texture and doing the cutout, the only other tools needed to complete the project were a pair of pliers to bend the wings and some glue to affix it to a clip. It turned out great!

Robot heart

For Halloween this year, I went as a robot, wearing a silver dress with a slowly pulsing LED heart glowing visibly under the fabric.

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The LED is a one watt white LED, which we’re running at about 50 mA. It has a wide viewing angle, and the star-shaped mount lies conveniently flat. The LED is wired up to the PCB with a pair of twisted magnet wires. Magnet wire is flexible and thin, which makes it hardly noticeable under clothing. It is controlled by ATtiny2313 (running the code from our Mac sleep light pumpkin project) and powered by three AAA batteries. The PCB corners were rounded off so it wouldn’t be stabby.

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The dress was fully lined, which made it very convenient for mounting electronics. I pinned a makeshift pocket onto the liner, and tucked the battery holder and PCB in the pocket. I could feel the battery holder switch and turn it on and off through the fabric.

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The LED was taped to the dress liner with medical tape to hold it in place. An extra piece or two of tape held the wires to make sure there was appropriate slack for movement. (A note on tape: use the good stuff. The cheap paper tape in the off-brand first aid kit only stuck to itself and the magnet wire. 3M plastic medical tape worked great and came off easily.) This makes it easy to disassemble after Halloween.

LED heart


You can find more costume projects in our Halloween Project Archive.

Pumpkin Faces for EggBot

Pumpkin Face

renegade_geek posted a set of Pumpkin Faces on thingiverse for the EggBot. They’re cleverly arranged in layers so that you can hide and show the different eye, nose and mouth options.

A collection of separate eyes, noses and mouths, each set on its own layer, for a customized jack-o-lantern/ghost face to be printed with the Eggbot. These were made to print on ping pong balls. You may need to adjust for eggs and other less regularly shaped items. I have included a “faces menu” PDF so that you can clearly review your choices. This was really helpful in a classroom situation.

Q and A with NanoBeam

Nanobeam

When we saw NanoBeam on Kickstarter, we had a hard time comprehending just how small it is. So we asked Hyrum if he could send us some pictures for a better sense of scale, and he obliged. Yes, it fits in a tic-tac box. After seeing just how teeny-tiny a 5 mm beam is (one quarter the cross sectional area of Maker Beam and one ninth of Open Beam), our next question was “What the heck?” So we asked what made him think of making such a tiny beam.

I just wanted some tiny beams to build a small robot. I looked all over the place but couldn’t find what I wanted. After some research, and talking to some extruding companies, I designed a beam that was so small it challenged all the rules of this manufacturing science. I made a few on my cnc mill before I commissioned the die, to be sure it was what I wanted.

Nanobeam

How did you find a factory to work with?

I combed the web and talked to a lot of companies. I finally found one that focused on small extrusions. I saw the amazingly small and precise work they were doing for companies like Boeing and 3M and I knew I found the company I needed.

Nanobeam

What kind of fasteners do you use for something this small?

I used the largest screw I could but they are still small. The size is M1.2; you will find these in some pairs of glasses. I’ve got 3 designs for the nuts, I am waiting on manufacturing samples for the last one before I decide for sure which I will use.

Nanobeam

We asked what he thought NanoBeam would be useful for.

Immediately, I see this making a splash with small robots, quad copters and electronic enclosures.  I also see it being great for diy wearables, scale models and crafts. I recently got feedback from a guy that wanted to use them as a frame, conductor and heat sink for an LED array. I can’t wait to see something like that. I’m going to get some stock without the black coating for this application.

We’re also very interested to see what people do with such a tiny extrusion! Thanks to Hyrum for answering our questions. You can find out more, and check out his designs (Open Source Hardware definition compliant) at the NanoBeam website and the Kickstarter campaign page.

Linkdump: October 2014